The nation's top police officer says the job of keeping tabs on Canadian extremists is draining police budgets, violence has become almost impossible to foresee and police need tools to react "decisively, quickly, preventatively."

One day after violence shook the core of Canada's capital, RCMP Commissioner Bob Paulson revealed dramatic footage from the shootings in which a gunman fatally shot a soldier and rampaged through Parliament Hill, before being gunned down himself. It was the second deadly attack on a soldier by a suspected extremist in Canada this week.

"We need to look at all options in terms of trying to deal with this sort of difficult and hard-to-understand threat," the police chief told reporters, laying out a detailed account of the case.

Story continues below advertisement

Commissioner Paulson, who has headed the Mounties since 2011, is the latest security official to say emerging threats are forcing a reconsideration of counterterrorism measures.

In coming days, Parliament – recently polarized by its vote to join a bombing campaign against Islamic State extremists in Iraq – will begin to consider Conservative legislation that aims to enhance the spying powers of federal agents.

Commissioner Paulson revealed what police know about the slain shooter, described as a 32-year-old drifter with "extremist belief" who was seeking to travel to Syria. Federal foot-dragging on supplying a new passport to Michael Zehaf-Bibeau, the police chief said, could have been a motivation behind the rampage.

"I think the passport figured prominently in his motives," Commissioner Paulson said, before adding "I'm not inside his head."

Mr. Zehaf-Bibeau, who had been recently living in Western Canada, is described by police, friends and public records as a man who became an Islamist extremist after a life of drug addiction and petty crime. Some acquaintances speculate he may have been mentally ill.

He is said to have checked into an Ottawa shelter on Oct. 2 and to have acquired a .30-calibre hunting rifle.

He had been banned from having a gun because of a long criminal history, and yet fatally shot Canadian Armed Forces Corporal Nathan Cirillo at the National War Memorial. Mr. Zehaf-Bibeau was shot dead after running into the Parliament's Centre Block.

Story continues below advertisement

Showing how quickly the rampage occurred on video, Commissioner Paulson said police had no opportunity to prevent the shooting of the soldier. The police boss would not confirm speculation Mr. Zehaf-Bibeau was inspired by Islamic State. But "according to some accounts, he was an individual who may have held extremist belief," he said.

There remains a possibility that Mr. Zehaf-Bibeau was a copycat killer. On Monday, Martin Couture-Rouleau – an Islamic convert who had been flagged by federal officials as a man too dangerous to be allowed to fly – was shot dead after killing a soldier with his car near Montreal.

Such suspects belong to a much bigger pool of extremists. Commissioner Paulson said the RCMP assigns about 180 detectives to national-security enforcement teams – yet he said the force has had to supplement this group by pulling an additional 250 officers off financial and organized crime probes. "It is a drain on resources," Commissioner Paulson said.

Recently an RCMP-led federal task force was formed to figure out ways to keep designated "high-risk travellers" from going to the Middle East, but the statistics about the travel bans and specific blocking mechanisms are not being revealed.

"There are 93 [high-risk travellers] at this time," Commissioner Paulson said. He said federal agents are taking a closer look at them in the wake of the shootings but "we haven't made any arrests thus far."

Mr. Zehaf-Bibeau had not been designated as such a suspect, but he was facing federal scrutiny as he filed for a new passport. It's unclear when his passport application was filed, or why he may have felt it was unduly delayed.

Story continues below advertisement

Police said they had some intelligence about him that was – and remains – hard to interpret. "This individual's e-mail was found in the hard drive of someone whom we've charged with a terrorist-related offence," Commissioner Paulson said.

Due to technical reasons, we have temporarily removed commenting from our articles. We hope to have this fixed soon. Thank you for your patience. If you are looking to give feedback on our new site, please send it along to feedback@globeandmail.com. If you want to write a letter to the editor, please forward to letters@globeandmail.com.

Welcome to The Globe and Mail’s comment community. This is a space where subscribers can engage with each other and Globe staff. Non-subscribers can read and sort comments but will not be able to engage with them in any way. Click here to subscribe.

Welcome to The Globe and Mail’s comment community. This is a space where subscribers can engage with each other and Globe staff. Non-subscribers can read and sort comments but will not be able to engage with them in any way. Click here to subscribe.